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@@ -1,73 +0,0 @@
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-# SPDX-License-Identifier: AGPL-3.0-or-later
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-# lint: pylint
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-# pyright: basic
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-"""Module for backward compatibility.
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-
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-"""
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-# pylint: disable=C,R
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-
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-
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-__all__ = ('cached_property',)
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-
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-
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-try:
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- from functools import cached_property # type: ignore
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-
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-except ImportError:
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-
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- # cache_property has been added in py3.8 [1]
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- #
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- # To support cache_property in py3.7 the implementation from 3.8 has been
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- # copied here. This code can be cleanup with EOL of py3.7.
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- #
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- # [1] https://docs.python.org/3/library/functools.html#functools.cached_property
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-
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- from threading import RLock
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-
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- _NOT_FOUND = object()
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-
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- class cached_property:
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- def __init__(self, func):
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- self.func = func
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- self.attrname = None
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- self.__doc__ = func.__doc__
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- self.lock = RLock()
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-
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- def __set_name__(self, owner, name):
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- if self.attrname is None:
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- self.attrname = name
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- elif name != self.attrname:
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- raise TypeError(
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- "Cannot assign the same cached_property to two different names "
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- f"({self.attrname!r} and {name!r})."
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- )
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-
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- def __get__(self, instance, owner=None):
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- if instance is None:
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- return self
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- if self.attrname is None:
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- raise TypeError("Cannot use cached_property instance without calling __set_name__ on it.")
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- try:
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- cache = instance.__dict__
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- except AttributeError: # not all objects have __dict__ (e.g. class defines slots)
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- msg = (
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- f"No '__dict__' attribute on {type(instance).__name__!r} "
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- f"instance to cache {self.attrname!r} property."
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- )
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- raise TypeError(msg) from None
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- val = cache.get(self.attrname, _NOT_FOUND)
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- if val is _NOT_FOUND:
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- with self.lock:
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- # check if another thread filled cache while we awaited lock
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- val = cache.get(self.attrname, _NOT_FOUND)
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- if val is _NOT_FOUND:
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- val = self.func(instance)
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- try:
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- cache[self.attrname] = val
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- except TypeError:
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- msg = (
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- f"The '__dict__' attribute on {type(instance).__name__!r} instance "
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- f"does not support item assignment for caching {self.attrname!r} property."
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- )
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- raise TypeError(msg) from None
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- return val
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